NB linear guide preload symbol and clearance
No. 170E-1 main catalogue pages Eng-36.
Effect of preload and rigidity
The rigidity of a linear system must be taken into consideration when it is to be used in hign-precision positioning devices or high-precision machinery.
Preloaded slide guides and ball splines, which use balls as the rolling elements, are available upon request to meet the need for greater rigidity.
If a force is applied to the bal elements without preload, an elastic deformation proportional to the applied force to the 2/3 jpower will result. Therefore, the elastic deformation is relatively large during the initial loading stage, however then becomes smaller as the load increases.
Preloading on the rolling elements absorbs the deformation of the block udner the same loading.
Types of preload and its specification
Preload is categorized into three ranges: standard, light, and medium for option. In the NB linear system, preload is applied by installing rolling elements that are slightly larger than standard. Therefor, the specification of the preload is expressed by a negative value.
No. 170E-1 main catalogue pages A-5., 22., 44., 80.
|
Preload |
Jel |
Működési környezet |
|---|---|---|
| Clearance |
T0 |
Light motion is required, installation errors to be absorbed. |
|
Standard |
- |
Miniature vibration is applied, accurate motion is required, moment is applied in a given direction. |
|
Light |
T1 |
Light vibration is applied, light torsional load is applied, moment is applied. |
|
Medium |
T2 |
Shock and vibration are applied, over-hang load is applied, torsional load is applied. |
Miniature (SEB, SEBS) slide guides
are available with a positive clearance (T0), a standard preload (blank), and light preload (T1).
| Size | T0 [µm] | Standard [µm] | T1 [µm] |
|---|---|---|---|
| SEB(S) 2 | +1~+3 | - | - |
| SEB(S) 3 | |||
| SEB(S) 5 | -1~0 | ||
| SEB(S) 7 | +3~+6 | -3~0 | -4~-2 |
| SEB(S) 9 | |||
| SEB(S) 12 | |||
| SEB(S) 15 | +4~+8 | -7~-3 | |
| SEB(S) 20 | |||
| SEB(S) 3W | +1~+3 | - | - |
| SEB(S) 5W | -1~0 | - | |
| SEB(S) 7W | +3~+6 | -3~0 | -4~-2 |
| SEB(S) 9W | |||
| SEB(S) 12W | |||
| SEB(S) 15W | +4~+8 | -7~-3 |
Miniature SER(S) slide guides
are available only with a standard (0 to slightly negative clearance) preload.
Normal (SGL, GL, SGW) slide guides
are available with a standard preload (blank), light preload (T1), and a medium preload (T2).
| Size |
Standard - [µm] |
Light T1 [µm] |
Medium T2 [µm] |
|---|---|---|---|
| SGL/GL 15 | -4~+2 | -12~-4 | - |
| SGL/GL 20 | -5~+2 | -14~-5 | -23~-14 |
| SGL/GL 25 | -6~+3 | -16~-6 | -26~-16 |
| SGL/GL 30 | -7~+4 | -19~-7 | -31~-19 |
| SGL/GL 35 | -8~+4 | -22~-8 | -35~-22 |
| SGL/GL 45 | -10~+5 | -25~-10 | -40~-25 |
| Size |
Standard - [µm] |
Light T1 [µm] |
Medium T2 [µm] |
|---|---|---|---|
| SGW 17 | -3~+2 | -7~-3 | - |
| SGW 21 | -4~+2 | -8~-4 | - |
| SGW 27 | -5~+2 | -11~-5 | - |
| SGW 35 | -8~+4 | -18~-8 | -28~-18 |